If the basic body structure is the same, yes you probably can ... consider, for example, that Victoria can go from a fairy to a heavy woman using the same bones. FLS's approach will indeed work if you only want one character, and don't intend to distribute it. However, if your intent is to create a character that you want to sell, or want to create more than one set of character morphs to be contained in the same CR2 file, you will have to apply each body part morph individually.